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Journal Cover Reactive and Functional Polymers
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   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 1381-5148
   Published by Elsevier Homepage  [3123 journals]
  • Block copolymer mediated generation of bimetallic Ni-Pd nanoparticles:
           Raman sensors of ethyl paraben and ciprofloxacin
    • Authors: Zarina Ansari; Tara Shankar Bhattacharya; Abhijit Saha; Kamalika Sen
      Pages: 1 - 11
      Abstract: Publication date: March 2018
      Source:Reactive and Functional Polymers, Volume 124
      Author(s): Zarina Ansari, Tara Shankar Bhattacharya, Abhijit Saha, Kamalika Sen
      In this research article, a highly simplified approach for the synthesis of nickel palladium bimetallic nanoparticles (Ni-PdNPs) is discussed. The synthesis method is of high novelty as it excludes involvement of any hazardous chemical and complicated laboratory set up. It is well known that generating a bimetallic nanoparticle involving nickel and palladium is a challenging task due to the difference in the reduction potential of the two metals E0 (V vs. SHE) for Ni2+ is −0.25V and Pd2+ is 0.95V respectively. One pot synthesis method of this material with a biocompatible polymer (PEG-PPG-PEG) which is mediated at room temperature is reported here for the first time. The synthesized particles are of size<5nm i.e., quantum dot dimension and were characterized by various analytical techniques such as absorption spectroscopy, transmission electron microscopy (TEM), dynamic light scattering (DLS), zeta potential, Fourier Transform Infra Red (FTIR) spectroscopy, powdered X-ray diffraction pattern (XRD), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. The elemental composition was investigated using the electron energy loss spectroscopy (EELS) measurement. In this work we report the Raman spectral feature of such a novel material. Also, its utilization as a sensor for pharmaceutically important materials like ciprofloxacin and ethyl paraben is reported here.

      PubDate: 2018-02-05T14:40:05Z
      DOI: 10.1016/j.reactfunctpolym.2018.01.002
      Issue No: Vol. 124 (2018)
       
  • Hybrid polymers containing brochantite/tenorite obtained using gel type
           anion exchanger
    • Authors: Elżbieta Kociołek-Balawejder; Ewa Stanisławska; Irena Jacukowicz-Sobala
      Pages: 12 - 19
      Abstract: Publication date: March 2018
      Source:Reactive and Functional Polymers, Volume 124
      Author(s): Elżbieta Kociołek-Balawejder, Ewa Stanisławska, Irena Jacukowicz-Sobala
      A gel type polystyrene/divinylbenzene anion exchanger containing quaternary ammonium groups was used as the macromolecular support for copper(II) compounds deposition, whereby novel hybrid anion exchangers were obtained. The anion exchanger in the OH− form was subjected to two-step transformation. In the first step, after reaction of supporting material with 0.1mol dm−3 CuSO4 solution load of Cu4(OH)6SO4 was introduced into the skeleton of the polymeric beads amounting to 60.0mg Cu g−1. In the second step, brochantite was converted into CuO using 0.1mol dm−3 NaOH solution. The final product contained about 29.0mg Cu g−1. Relatively high degree of transformation of brochantite into tenorite was achieved when the wet semi-finished product was introduced into the NaOH solution at ambient temperature. The presence of brochantite and tenorite was confirmed by FTIR and XRD analyses. In the present studies we have shown that gel type matrix of polymeric beads was crucial to the pathway of cupric compounds deposition. Evaluation of sorptive, photocatalytic and biocidic properties of these novel materials will be presented and discussed in separate works.

      PubDate: 2018-02-05T14:40:05Z
      DOI: 10.1016/j.reactfunctpolym.2018.01.004
      Issue No: Vol. 124 (2018)
       
  • PDMS tri-block copolymers bearing quaternary ammonium salts for epidermal
           antimicrobial agents: Synthesis, surface adsorption and
           non-skin-penetration
    • Authors: Yufeng Lei; Shengwen Zhou; Chenyun Dong; Anqiang Zhang; Yaling Lin
      Pages: 20 - 28
      Abstract: Publication date: March 2018
      Source:Reactive and Functional Polymers, Volume 124
      Author(s): Yufeng Lei, Shengwen Zhou, Chenyun Dong, Anqiang Zhang, Yaling Lin
      Quaternary ammonium salts are widely used as epidermal and topical antimicrobial agents in medical treatments due to their broad activity, excellent performance and ready availability. However, their epidermal application has revealed many noticeable disadvantages, including short-term functionality, environmental toxicity, rapid antimicrobial resistance and skin penetration. Here, a series of tri-block copolymers grafted with dimethylaminopropyl benzyl chloride and based on a polydimethylsiloxane (PDMS) backbone, referred to as PDMS-b-(PDMS-g-BC)-g-PDMS, were prepared with well-controlled chain length and cationic grafting content. The quaternary ammonium salt-containing polymers were effective antimicrobial agents against epidermal pathogenic microbes, such as E. coli, S. albus and C. albicans. By incorporating hydrophilic and antimicrobial quaternary ammonium salt groups into the hydrophobic PDMS backbones, the amphiphilic tri-block copolymers were water-soluble but capable of assembling onto different surfaces, driven by electrostatic attraction or hydrophobic repulsion, which yielded long-term functionality on the surface. Moreover, the enlarged molecular size prevented penetration though full-thickness rat skins. These findings suggest a promising application of polymeric quaternary ammonium salts with hydrophobic moieties as epidermal antimicrobial agents.
      Graphical abstract image

      PubDate: 2018-02-05T14:40:05Z
      DOI: 10.1016/j.reactfunctpolym.2018.01.007
      Issue No: Vol. 124 (2018)
       
  • Soft hydrazone crosslinked hyaluronan- and alginate-based hydrogels as 3D
           supportive matrices for human pluripotent stem cell-derived neuronal cells
           
    • Authors: Jennika Karvinen; Tiina Joki; Laura Ylä-Outinen; Janne T. Koivisto; Susanna Narkilahti; Minna Kellomäki
      Pages: 29 - 39
      Abstract: Publication date: March 2018
      Source:Reactive and Functional Polymers, Volume 124
      Author(s): Jennika Karvinen, Tiina Joki, Laura Ylä-Outinen, Janne T. Koivisto, Susanna Narkilahti, Minna Kellomäki
      Regenerative medicine, especially cell therapy combined with a supportive biomaterial scaffold, is considered to be a potential treatment for various deficits in humans. Here, we have produced and investigated the detailed properties of injectable hydrazone crosslinked hyaluronan-polyvinyl alcohol (HA-PVA) and alginate-polyvinyl alcohol (AL-PVA) hydrogels to be used as a supportive biomaterial for 3D neural cell cultures. To the best of our knowledge, this is the first time the polymerization and properties of hydrazone crosslinked AL-PVA hydrogel have been reported. The effect of the degree of substitution and molecular weight of the polymer components as well as the polymer concentration of the hydrogel on the swelling, degradation and mechanical properties of the hydrogels is reported. Furthermore, we studied the effect of the above parameters on the growth of human pluripotent stem cell-derived neuronal cells. The most neural cell supportive HA-PVA hydrogel was composed of high molecular weight HA component with brain-mimicking mechanical properties and decreased polymer concentration. AL-PVA hydrogel, with stiffness quite similar to brain tissue, was also shown to be similarly supportive. Neuronal spreading and 3D network formation was enhanced inside the softest hydrogels.

      PubDate: 2018-02-05T14:40:05Z
      DOI: 10.1016/j.reactfunctpolym.2017.12.019
      Issue No: Vol. 124 (2018)
       
  • Formulation and evaluation of epinephrine-loaded poly(acrylic
           
    • Authors: Adhimoorthy Prasannan; Hsieh-Chih Tsai; Ging-Ho Hsiue
      Pages: 40 - 47
      Abstract: Publication date: March 2018
      Source:Reactive and Functional Polymers, Volume 124
      Author(s): Adhimoorthy Prasannan, Hsieh-Chih Tsai, Ging-Ho Hsiue
      Conventional eyedrops commonly used to deliver ophthalmologic treatments do not provide a sustained delivery of the drug, since a large portion of the intended dose is lost through eye drainage immediately following application. Micrometric sized crosslink gel based on copolymers incorporating thermal-sensitive copolymers were proposed for use in ophthalmic drug delivery. Eyedrops based on a thermoresponsive polymer were developed by mixing poly(acrylic acid-graft-N-isopropylacrylamide) (PAAc-graft-PNIPAAm) with PAAc-co-PNIPAAm gel and incorporating [3H]-epinephrine for in vitro evaluation of ophthalmic drug release. Polymeric eyedrops are clear solutions at room temperature but undergo partial solidification to a soft thin film on coming into contact with the corneal surface. On evaluation of the in vitro release kinetics of the embedded [3H]-epinephrine, PAAc-graft-PNIPAAm was found to exhibit faster drug release, while the mixture of PAAc-graft-PNIPAAm and PAAc-co-PNIPAAm gel showed a more sustained release profile and identifying the anomalous transport mechanism as a key factor. Intraocular pressure (IOP) was monitored by administration of epinephrine in polymeric eyedrops effectively reduced IOP for 36h, which is a considerable prolongation of the effect compared to the 8-h IOP decrease observed following administration via traditional eyedrops. Overall, our results indicate that the kinetics of drug release from the polymeric eyedrops are determined by crosslinking density, which affects the formation of capillary networks in the polymer matrix and thereby regulates drug diffusion into the polymeric network, hence considered as feasible approach to controlled drug release in ophthalmic drug delivery.
      Graphical abstract image

      PubDate: 2018-02-05T14:40:05Z
      DOI: 10.1016/j.reactfunctpolym.2018.01.001
      Issue No: Vol. 124 (2018)
       
  • Significantly enhanced CH4 permeability base on
           poly(styrene-b-butadiene-b-styrene)-poly(dimethylsiloxane-co-methylhydrosiloxane)
           crosslinked membranes
    • Authors: Xing Yang; Tengyang Zhu; Zongxiang Xu; Haiquan Shan; Jujie Luo
      Pages: 48 - 54
      Abstract: Publication date: March 2018
      Source:Reactive and Functional Polymers, Volume 124
      Author(s): Xing Yang, Tengyang Zhu, Zongxiang Xu, Haiquan Shan, Jujie Luo
      Poly(styrene-b-butadiene-b-styrene) triblock copolymer (SBS) crosslinked membranes containing poly(dimethylsiloxane-co-methylhydrosiloxane) (PDMS-co-PMHS) were prepared by hydrosilylation reaction toward CH4/N2 separation. The effect of an additive amount of PDMS-co-PMHS on the structure, morphology, and thermodynamic stability of crosslinked membranes were investigated by using FT-IR, SEM and TGA. Soxhlet extraction experiments were also performed to explore the crosslinking degree of membranes. In this work, the single-gas permeability of CH4 and N2 was measured using the constant volume–variable pressure method. Our experimental results showed that crosslinked membranes can significantly enhance CH4 permeability with increasing PDMS-co-PMHS content, whereas the CH4/N2 selectivity remains unchanged. Among these crosslinked membranes, the SBS-c-PDMS-co-PMHS-70 membrane exhibited optimal CH4 permeability at room temperature and the pressure of 1bar. Specifically, the CH4 permeability was >10-folds higher than that of the SBS membranes (37.6 barrer versus 443.6 barrer). Moreover, investigation of the effect of test temperature on the gas permeation of crosslinked membranes revealed a preferable CH4 permeability at 55°C and 1bar, at which the CH4 permeability reaches 679.2 barrer without a substantial compromise in selectivity.
      Graphical abstract image

      PubDate: 2018-02-05T14:40:05Z
      DOI: 10.1016/j.reactfunctpolym.2018.01.009
      Issue No: Vol. 124 (2018)
       
  • Design of porous strong base anion exchangers bearing N,N-dialkyl
           2-hydroxyethyl ammonium groups with enhanced retention of Cr(VI) ions from
           aqueous solution
    • Authors: Ecaterina Stela Dragan; Doina Humelnicu; Maria Valentina Dinu
      Pages: 55 - 63
      Abstract: Publication date: March 2018
      Source:Reactive and Functional Polymers, Volume 124
      Author(s): Ecaterina Stela Dragan, Doina Humelnicu, Maria Valentina Dinu


      PubDate: 2018-02-05T14:40:05Z
      DOI: 10.1016/j.reactfunctpolym.2018.01.010
      Issue No: Vol. 124 (2018)
       
  • Synthesis and characterization of poly (ionic liquid) derivatives of
           N-alkyl quaternized poly(4-vinylpyridine)
    • Authors: Ximena Briones O.; Ricardo A. Tapia; Paola R. Campodónico; Marcela Urzúa; Ángel Leiva; Renato Contreras; Javier González-Navarrete
      Pages: 64 - 71
      Abstract: Publication date: March 2018
      Source:Reactive and Functional Polymers, Volume 124
      Author(s): Ximena Briones O., Ricardo A. Tapia, Paola R. Campodónico, Marcela Urzúa, Ángel Leiva, Renato Contreras, Javier González-Navarrete
      The main motivation of this work is to obtain poly (ionic liquids) (PILs) derived from poly (4-vinyl pyridine) of different hydrophobic character containing BF4 −, PF6 −, (CF3SO2)2 N− and CF3SO3 − as counterions. PILs were synthesized from N-alkyl quaternized poly(4-vinylpyridine) P-4VP+-CnBr− with different alkyl chain length, n =2, 4, 5 and different molecular weights (60.000 and 160.000g/mol). The systems obtained were compared with the polyelectrolyte of origin, i.e., the N-alkyl quaternized poly(4-vinylpyridine). The molecular characterization of PILs was obtained by FT-IR, 1H NMR and 19F NMR. Moreover, the thermal analysis of these systems was by carried out by differential scanning calorimetry (DSC) and thermogravimetry (TGA) techniques. Thermal degradation profiles obtained from TGA measurements, varied according to the alkyl chain length, which in turn influenced the obtained values of glass transition temperature (Tg), due to greater or lesser segmental movement of the alkyl chain. The results obtained for the PILs studied were analysed according to alkyl chain length, molecular weight and counter-anion effects. Additionally, P-4VP+-C4 BF4 − was used in a preliminary study of chromium (VI) removal from aqueous solution, showing a 72.2% removal of Cr (VI).

      PubDate: 2018-02-05T14:40:05Z
      DOI: 10.1016/j.reactfunctpolym.2018.01.003
      Issue No: Vol. 124 (2018)
       
  • Size-tunable protein–polymer hybrid carrier for cell internalization
    • Authors: Chaeyeon Lee; Ji Eun Choi; Gil Yong Park; Taeheon Lee; Jinku Kim; Seong Soo A. An; Jae Kwang Song; Hyun-jong Paik
      Pages: 72 - 76
      Abstract: Publication date: March 2018
      Source:Reactive and Functional Polymers, Volume 124
      Author(s): Chaeyeon Lee, Ji Eun Choi, Gil Yong Park, Taeheon Lee, Jinku Kim, Seong Soo A. An, Jae Kwang Song, Hyun-jong Paik
      Graphical abstract image

      PubDate: 2018-02-05T14:40:05Z
      DOI: 10.1016/j.reactfunctpolym.2018.01.006
      Issue No: Vol. 124 (2018)
       
  • Design of copolymer PLA-PCL electrospun matrix for biomedical applications
    • Authors: S. Pisani; R. Dorati; B. Conti; T. Modena; G. Bruni; I. Genta
      Pages: 77 - 89
      Abstract: Publication date: March 2018
      Source:Reactive and Functional Polymers, Volume 124
      Author(s): S. Pisani, R. Dorati, B. Conti, T. Modena, G. Bruni, I. Genta
      Electrospinning is a quite consolidated technique to produce polymer nanofibrous matrices whose nanostructured morphology received great interest for application in the biomedical field i.e. in manufacturing matrices for tissue regeneration. Purpose of the work to design electrospun matrices made of Poly-l-lactide-co-poly-ε-caprolactone (PLA-PCL) 70:30M ratio and their thoroughly physico-chemical and functional characterization. The ultimate goal of the research work is to obtain electrospun matrices suitable for circular substitution of esophageal defects. However the paper deals with very preliminary investigation mainly on electrospinning process and physical-chemical characterization of the electrospun matrices. The investigation on electrospinning process conditions involves polymer starting solution concentration between 20% w/v and 25% w/v, viscosity and surface tension, but also process parameters of electrospinning apparatus in order to optimize them at achieving homogeneous and reproducible nanofibers. The optimized electrospun matrices are characterized for their cytocompatibility, morphology (SEM analysis), polymer molecular structure in the solid state (FT-IR analysis) and thermal behavior (DSC analysis) and mechanical properties. In vitro degradation test is performed to evaluate electrospun matrix biodegradability. Results show good cytocompatibility for all polymer concentrations and electrospinning times. Moreover, the electrospun matrices biodegradation is slower with respect to matrices made by solvent casting method. The behavior is related to modifications in the polymer solid state and to polymer chains structure.

      PubDate: 2018-02-05T14:40:05Z
      DOI: 10.1016/j.reactfunctpolym.2018.01.011
      Issue No: Vol. 124 (2018)
       
  • Surface-activated anion exchange resins for synthesis and immobilization
           of gold and palladium nano- and microstructures
    • Authors: Piotr Cyganowski; Anna Leśniewicz; Izabela Polowczyk; Jacek Chęcmanowski; Tomasz Koźlecki; Paweł Pohl; Dorota Jermakowicz-Bartkowiak
      Pages: 90 - 103
      Abstract: Publication date: March 2018
      Source:Reactive and Functional Polymers, Volume 124
      Author(s): Piotr Cyganowski, Anna Leśniewicz, Izabela Polowczyk, Jacek Chęcmanowski, Tomasz Koźlecki, Paweł Pohl, Dorota Jermakowicz-Bartkowiak
      A series of surface-activate anion exchange resins, bearing amino functionalities, were employed in processes of multiple adsorption and desorption of AuCl4 −, PtCl6 2− and PdCl4 2− from solutions in 0.1 and 3mol∙L−1 HCl. The resins with ethylenediamine (EDA) and 1-(2-aminoethyl)piperazine (AEP) functionalities efficiently removed up to 100wt% of the noble metals, however, instead expected total elution, they revealed only up to 50wt% of desorption. The phenomenon was caused by the fact, that the anion exchange resins revealed an ability to reduce ionic forms of gold and palladium to their nano- and microparticles creating colloids and nanocomposites. For that reason the generated metallic forms were investigated using X-Ray Diffraction (XRD), Dynamic Light Scattering (DLS) and Scanning Electron Microscopy (SEM). The size of the obtained structures was in range of 50–1000nm, however, because reduction involves the transfer of an electron from a donor nitrogen it is dependent on the number of nitrogen atoms in amino ligands. A very close look at the changes in the resins' chemical structures has been taken using Fourier Transformation Infrared Spectroscopy allowing to determine a possible reason of the reduction.

      PubDate: 2018-02-05T14:40:05Z
      DOI: 10.1016/j.reactfunctpolym.2018.01.013
      Issue No: Vol. 124 (2018)
       
  • Enhanced hemocompatibility of flat and hollow fiber membranes via a
           heparin free surface crosslinking strategy
    • Authors: Hui Wang; Jinglong Li; Fu Liu; Tiantian Li; Yun Zhong; Haibo Lin; Jidong He
      Pages: 104 - 114
      Abstract: Publication date: March 2018
      Source:Reactive and Functional Polymers, Volume 124
      Author(s): Hui Wang, Jinglong Li, Fu Liu, Tiantian Li, Yun Zhong, Haibo Lin, Jidong He
      Insufficient hemocompatibility is challenging for current dialysis membranes. The current modification methods have some limitations in effectiveness, practicality and cost. Herein, we develop a heparin-free crosslinking approach to enhance the hemocompatibility of both the flat (polylactide) and hollow fiber (polysulfone) membranes with heparin-mimicking surface. Poly (triethoxyvinylsilane-N-vinyl-2-pyrrolidone) (P (VTES-VP)) is first introduced to the membrane surface to improve the hydrophilicity, which is facilitated to the adsorption and further crosslinking of poly (triethoxyvinylsilane-Acrylic acid-Sodium 4-vinylbenzenssulfonate) (P(VTES-AA-SSNa)). The mixture of N, N-dimethylacetamide (DMAc) and water was modulated for good solubility, swelling and adsorption of precopolymer. The chemical structure of the heparin-mimicking membrane was confirmed by attenuated total reflectance Fourier transform infrared spectra (FTIR-ATR), X-ray photoelectron spectroscopy (XPS), weight measurement and scanning electron microscopy (SEM). The hydrophilicity was improved by the heparin-mimicking surface. Moreover, the heparin-mimicking membranes presents higher platelet resistance, prolonged coagulation time (APTT for ~180.1s), decreased Plasma fibrinogen (FIB for ~122mg/dL), and suppressed complement activation. More importantly, the heparin-free crosslinking approach can be utilized to significantly enhance the hemocompatibility of commercial PSF hollow fiber membranes, indicating its potential application in heparin free dialyzers.

      PubDate: 2018-02-05T14:40:05Z
      DOI: 10.1016/j.reactfunctpolym.2018.01.008
      Issue No: Vol. 124 (2018)
       
  • Tailoring polyvinyl alcohol with triazinanes and formaldehyde
    • Authors: Fusun Seyma Gungor; Baris Kiskan
      Pages: 115 - 120
      Abstract: Publication date: March 2018
      Source:Reactive and Functional Polymers, Volume 124
      Author(s): Fusun Seyma Gungor, Baris Kiskan
      Cross-linking of polyvinyl alcohol (PVA) was achieved by using functional 1,3,5-triazinanes and formaldehyde as cross-linking agents. This method can be considered as an alternative to acetalization of PVA by monoaldehydes. The gels obtained with the triazinane method exhibited dimensional stability and resistance against acids. Control experiments were performed to have a better insight of the gelation process. The products of control experiments and obtained gels were characterized spectroscopically by FTIR and 1H NMR and thermally by DSC. Moreover, swelling in water and acid stability of gels were investigated and compared to the PVA–formaldehyde system.
      Graphical abstract image

      PubDate: 2018-02-05T14:40:05Z
      DOI: 10.1016/j.reactfunctpolym.2018.01.014
      Issue No: Vol. 124 (2018)
       
  • Biomimetic recognition and peptidase activities of transition state
           analogue imprinted chymotrypsin mimics
    • Authors: Divya Mathew; Benny Thomas; K.S. Devaky
      Pages: 121 - 128
      Abstract: Publication date: March 2018
      Source:Reactive and Functional Polymers, Volume 124
      Author(s): Divya Mathew, Benny Thomas, K.S. Devaky
      The first peptidolysis reaction utilizing transition state analogue imprinted polymer was demonstrated utterly in the viewpoint of size and shape-selective substrate recognition. The enzyme mimic polymer was synthesized from the amino acid triad histidine, aspartic acid and serine in presence of phenyl-1-(N-benzyloxycarbonylamino)-2-(phenyl)ethyl phosphonate transition state analogue (TSA) by molecular imprinting technique. The polymer catalyst synthesized exhibited high selectivity and performed as a reliable tool for peptidolytic reactions. The peptidase activity of the enzyme mimic polymer catalyst was investigated by following the hydrolysis of dipeptides spectrophotometrically at 207nm and the kinetic parameters, rate acceleration k acc and imprinting efficiency k im , were evaluated. The imprinted peptidase displayed a rate acceleration of 1.67×103 contrasted with the uncatalyzed peptidolysis and an imprinting efficiency of 45 over the non-imprinted control polymer. The artificial peptidase amazingly promoted the hydrolysis of dipeptides having Phe/Tyr amino acid as the C-terminal residues discriminating chymotrypsin specific and non-specific substrates. The mimic exhibited higher rate acceleration and substrate specificity towards peptides compared to amino acid p-nitroanilides. Despite the fact that natural enzyme is much superior to the MIP catalyst in hydrolase activities, the mimic portrays high thermal stability, prolonged life span and unrivaled recyclability and reusability.

      PubDate: 2018-02-05T14:40:05Z
      DOI: 10.1016/j.reactfunctpolym.2018.01.005
      Issue No: Vol. 124 (2018)
       
  • Synthesis of photo-responsive chitosan-cinnamate for efficient entrapment
           of β-galactosidase enzyme
    • Authors: M. Monier; I. Youssef; D.A. Abdel-Latif
      Pages: 129 - 138
      Abstract: Publication date: March 2018
      Source:Reactive and Functional Polymers, Volume 124
      Author(s): M. Monier, I. Youssef, D.A. Abdel-Latif
      A modified photo-crosslinkable chitosan cinnamate (CS-CN) bio-polymer was synthesized via functionalization of the main active –NH2 and –OH groups of chitosan using cinnamoyl chloride. The chemical structure of the manufactured bio-polymer was elucidated using instrumental techniques including FTIR and NMR spectra. The obtained photo-active CS-CN was cross-linked upon irradiation with the UV light and the performed photo-crosslinking was monitored using UV–vis light spectra. Moreover, XRD and SEM were respectively utilized to investigate both crystalline and morphological structures of the cross-linked bio-polymer. The obtained CS-CN bio-polymer was successfully employed as a polymeric support for β-galactosidase immobilization via entrapment technique. The entrapped β-galactosidase maintains around 80% of its initial activity and displayed a considerable stability against temperature and pH changes in comparison with the native soluble enzyme form. In addition, the kinetic studies showed an expected elevation of K m along with lowering of v o values after immobilization reflecting a lower enzyme-substrate affinity. However, the reusability experiments indicated that the entrapped enzyme maintains approximately 88% of its activity after 8 reuse cycles, which reveal the value of the performed immobilization technique especially in economic terms.

      PubDate: 2018-02-05T14:40:05Z
      DOI: 10.1016/j.reactfunctpolym.2018.01.012
      Issue No: Vol. 124 (2018)
       
  • Structural effects of highly π-conjugated mesogenic Schiff-base moiety on
           the cationic polymerization of benzoxazine and formation of ordered
           morphologies
    • Authors: Huan Liu; Qing-Quan Liu; Li Tian; Lin-Yan Wang; Kai Xu; Qian-Xin Chen; Bao-Li Ou
      Pages: 139 - 148
      Abstract: Publication date: March 2018
      Source:Reactive and Functional Polymers, Volume 124
      Author(s): Huan Liu, Qing-Quan Liu, Li Tian, Lin-Yan Wang, Kai Xu, Qian-Xin Chen, Bao-Li Ou
      A Schiff-base moiety was introduced into the chemical structure of benzoxazine through the Mannich reaction. With alternative imine groups (CN) and benzene rings in the chain segment, these highly π-conjugated systems favored the formation of strong intermolecular hydrogen bonds to the hydroxyl groups generated during polymerization, leading to a thermally initiated cationic polymerization mechanism. Compared with the bisphenol-A-based benzoxazine, the benzoxazine with the Schiff-base moiety needs higher energy to facilitate the realization of polymerization and to increase polymerization degree. In addition to the influences on the polymerization, the highly π-conjugated Schiff-base acting as a mesogenic moiety is found to form liquid crystal (LC) phases, like the nematic phase and smectic phase. Interestingly, some LC-rich domains can be stabilized by the polybenzoxazine network, which will contribute to form nitrogen-rich ordered porous carbon at the carbonization stage. For N2 and CO2 adsorption–desorption process, the carbon exhibits an enhanced CO2 adsorption performance, suggesting their capture and separation capacity for CO2.

      PubDate: 2018-02-05T14:40:05Z
      DOI: 10.1016/j.reactfunctpolym.2018.01.015
      Issue No: Vol. 124 (2018)
       
  • Comparative study on antimicrobial activity and biocompatibility of
           N-selective chitosan derivatives
    • Authors: Prasanna S. Bakshi; D. Selvakumar; K. Kadirvelu; N.S. Kumar
      Pages: 149 - 155
      Abstract: Publication date: March 2018
      Source:Reactive and Functional Polymers, Volume 124
      Author(s): Prasanna S. Bakshi, D. Selvakumar, K. Kadirvelu, N.S. Kumar
      N-selective derivatives of chitosan (CH) namely, N-methyl chitosan (NMC), trimethyl chitosan (TMC), diethyl methyl chitosan (DEMC) and carboxymethyl chitosan (CMC) were synthesized to study the effects of alkylation on antimicrobial property and biocompatibility. The derivatives were characterized by FT-IR confirming O-free alkyl substitution. XRD studies showed reduction in crystallinity and zeta potential measurement proved the increase in positive charges upon alkylation. Antimicrobial activity was observed to be in the order of DEMC<CMC<CH<NMC<TMC. MTT assay revealed that the modified chitosans were non-cytotoxic to primary normal human epidermal keratinocytes. Chitosan derivatives were tested using EpiDerm™ Skin Irritation Test as per OECD TG 439 and were categorized as non-irritants. Zebrafish embryo viability test was used to study the toxicity of the modified chitosans and LC50 for the samples in zebrafish embryo ranged from 20 to 50μg/mL. Results showed that amongst the alkyl derivatives, O-methyl free N,N,N–trimethyl chitosan (TMC) is the potential candidate material with enhanced antimicrobial property and biocompatibility. Herein, we report the first results of using chitosan or its derivatives in the EpiDerm in vitro skin irritation test. The four derivatives of chitosan are compared on a single platform for their physicochemical, biological and biocompatible properties.

      PubDate: 2018-02-05T14:40:05Z
      DOI: 10.1016/j.reactfunctpolym.2018.01.016
      Issue No: Vol. 124 (2018)
       
  • Self-assembling unsymmetrical bis-ureas
    • Authors: Kelly Melia; Barnaby W. Greenland; Daniel Hermida-Merino; Lewis R. Hart; Ian W. Hamley; Howard M. Colquhoun; Andrew T. Slark; Wayne Hayes
      Pages: 156 - 161
      Abstract: Publication date: March 2018
      Source:Reactive and Functional Polymers, Volume 124
      Author(s): Kelly Melia, Barnaby W. Greenland, Daniel Hermida-Merino, Lewis R. Hart, Ian W. Hamley, Howard M. Colquhoun, Andrew T. Slark, Wayne Hayes
      Model compounds of unsymmetrical bis-ureas have been designed and synthesised to investigate and further understand the formation of supramolecular polymer arrays. Association constants (<200M−1) for the bis-ureas have been determined by 1H NMR spectroscopy, and further characterised by optical spectroscopy. In addition, SAXS analysis of the bulk material reveals the formation of different highly ordered structures demonstrating complex hydrogen bonding of these unsymmetrical materials. Thermal transitions are also observed in some examples of unsymmetrical bis-ureas near to the melting point, as evidenced by double endotherms in DSC analysis. We also propose a re-organisation mechanism whereby the supramolecular array is first altered before proceeding to melt which is supported by variable temperature SAXS analysis.
      Graphical abstract image

      PubDate: 2018-02-05T14:40:05Z
      DOI: 10.1016/j.reactfunctpolym.2018.01.017
      Issue No: Vol. 124 (2018)
       
  • Covalent immobilization of organophosphorus hydrolase enzyme on chemically
           modified cellulose microfibers: Statistical optimization and
           characterization
    • Authors: Meisam Sharifi; Seyed-Mortaza Robatjazi; Minoo Sadri; Jafar Mohammadian Mosaabadi
      Pages: 162 - 170
      Abstract: Publication date: March 2018
      Source:Reactive and Functional Polymers, Volume 124
      Author(s): Meisam Sharifi, Seyed-Mortaza Robatjazi, Minoo Sadri, Jafar Mohammadian Mosaabadi
      Organophosphorus hydrolase (OPH) from Flavobacterium ATCC 27551 was covalently immobilized on epoxy modified plant cellulose powder. The Taguchi method was applied to optimize the conditions of cellulose activation and binding of the OPH to the carrier surface. The chemical modification of cellulose by covalent coupling with 1, 4-butanediol diglycidyl ether was demonstrated using the FTIR technique. TEM analysis proved good linkage of the OPH over the support surface. At the identified optimum condition of affecting parameters, the activity yield of immobilized OPH on the modified cellulose was found to be 68.32%. The kinetic parameters, K m and V max values, were calculated and it was determined that the catalytic efficiency of the immobilized OPH was about 4.85-fold lower than that of free enzyme. The storage, thermal, and pH stabilities of the immobilized OPH were improved compared with free counterpart. The results revealed that after incubation for 24 h at 55 °C, the soluble and immobilized OPH retained 8% and 35% of their initial activities, respectively. Furthermore, the immobilized OPH showed a 59% residual activity when used ten times repeatedly. Therefore, plant cellulose as a low-cost carrier has shown excellent properties for enzyme immobilization to be used as biocatalytic material in large scale applications.

      PubDate: 2018-02-05T14:40:05Z
      DOI: 10.1016/j.reactfunctpolym.2018.01.019
      Issue No: Vol. 124 (2018)
       
  • Tuning the associative properties and micelles geometry by stepwise
           quaternization of PDMAEMA
    • Authors: Ecaterina Stela Dragan; Maria Bercea; Liviu Sacarascu
      Pages: 171 - 180
      Abstract: Publication date: March 2018
      Source:Reactive and Functional Polymers, Volume 124
      Author(s): Ecaterina Stela Dragan, Maria Bercea, Liviu Sacarascu
      We report on the synthesis and characterization of amphiphile copolymers derived from poly(N,N-dimethylaminoethyl methacrylate) (PDMAEMA) generated by the stepwise quaternization of PDMAEMA, first with 1-hexadecyl bromide (HDB) and then with benzyl chloride (BC). Amphiphile copolymers consisting of hydrophile blocks separated by hydrophobe units were thus prepared in a predictable manner. The chemical structure of the hydrophobically modified polycations was confirmed by FTIR and 1H NMR spectroscopy, and by elemental analysis. The behavior in salt-free aqueous solutions was investigated by viscometry at 25 °C, rheological investigations at different temperatures, and by SAXS measurements. The steady shear measurements revealed an aggregation during the flow at moderate shear rates, the amplitude of this phenomenon depending on the hydrophobic/hydrophilic balance. The clusters are formed due to the intermolecular interactions and they grow as the shear rate is approaching 1 s−1. For the temperatures between 45 °C and 65 °C, the shear forces determine an expansion of the macromolecules that tend to orient in the flow direction and favor either a better interaction of the hydrophilic groups with the water molecules, or the manifestation of hydophobic interactions. The associative properties and the micelles geometry were tuned by the content and distribution of the hexadecyl groups.

      PubDate: 2018-02-05T14:40:05Z
      DOI: 10.1016/j.reactfunctpolym.2018.01.018
      Issue No: Vol. 124 (2018)
       
  • Copolymerization of bisphthalonitrile/benzoxazine blends: Curing behavior,
           thermomechanical and thermal properties
    • Authors: Yi-le Xu; Abdul Qadeer Dayo; Mehdi Derradji; Jun Wang; Wen-bin Liu; Sha Song; Tao Tang
      Pages: 97 - 105
      Abstract: Publication date: February 2018
      Source:Reactive and Functional Polymers, Volume 123
      Author(s): Yi-le Xu, Abdul Qadeer Dayo, Mehdi Derradji, Jun Wang, Wen-bin Liu, Sha Song, Tao Tang
      A high-performance copolymer was successfully prepared by blending bisphenol-A based bisphthalonitrile monomer (BAPh) with phenol-aniline-based benzoxazine monomer (P-a). The obtained copolymers exhibited excellent thermal stability and thermomechanical properties. The Fourier transform infrared (FTIR) spectra of BAPh/P-a 5:5 system at different curing procedure proved the curing reaction mechanism. In addition, differential scanning calorimetry (DSC) curves showed that the curing reaction of the BAPh was induced by the active hydroxyl produced by the ring-opening polymerization of P-a; compared to the neat monomers, the curing temperature of the copolymer decreased and the curing speed improved. The evolution of thermal gravimetric analysis (TGA) curves revealed that the poly(BAPh/P-a)-5:5 displayed highest T 5% , T 10% , and char yield. The dynamic mechanical analysis (DMA) proved that the glass transition temperature and storage modulus of copolymers with the BAPh monomer as the matrix increased with the content of P-a increase, while copolymers with P-a as the matrix obtained nearly same results. The poly(BAPh/P-a) -5:5 exhibited best thermal and thermomechanical properties among different composition copolymers.

      PubDate: 2018-02-05T14:40:05Z
      DOI: 10.1016/j.reactfunctpolym.2017.12.013
      Issue No: Vol. 123 (2018)
       
  • Recovery of Au(III) from an aqueous solution by
           aminopropyltriethoxysilane-functionalized lignocellulosic based adsorbents
           
    • Authors: Norasikin Saman; Muhammad Usman Rashid; Jimmy Wei Ping Lye; Hanapi Mat
      Pages: 106 - 114
      Abstract: Publication date: February 2018
      Source:Reactive and Functional Polymers, Volume 123
      Author(s): Norasikin Saman, Muhammad Usman Rashid, Jimmy Wei Ping Lye, Hanapi Mat
      Lignocellulosic coconut pith (LCP) was functionalized with 3-aminopropyltriethoxysilane (APS) towards preparing aminopropyltriethoxysilane-functionalized lignocellulosic coconut pith (APS-LCP) adsorbents for high adsorption affinity towards Au(III) ions. The functionalization was confirmed by morphological, functional groups and thermal analyses. The Au(III) adsorption results show that the APS-LCP possessed much better Au(III) adsorption than LCP and both exhibited endothermic process. The Au(III) adsorption isotherm data fitted well to the Langmuir isotherm having the maximum adsorption capacity of 215.68mgg−1 and 261.36mgg−1, respectively, for the LCP and APS-LCP at 30°C. The kinetic model analysis showed that the overall adsorption process was controlled by film diffusion, while the active site chemical interactions (e.g. ion exchange, chelation and reduction) were best described by the pseudo-second order kinetic model. Adsorption-desorption experiment revealed that the APS-LCP could be regenerated with minimum loss of the adsorption capacity. These results demonstrate the potential application of lignocellulosic materials as adsorbents through an appropriate modification for adsorptive recovery of Au(III) ions from an aqueous solution.

      PubDate: 2018-02-05T14:40:05Z
      DOI: 10.1016/j.reactfunctpolym.2017.12.015
      Issue No: Vol. 123 (2018)
       
  • Lignin-polyurea microcapsules with anti-photolysis and sustained-release
           performances synthesized via pickering emulsion template
    • Authors: Yuxia Pang; Xin Li; Shengwen Wang; Xueqing Qiu; Dongjie Yang; Hongming Lou
      Pages: 115 - 121
      Abstract: Publication date: February 2018
      Source:Reactive and Functional Polymers, Volume 123
      Author(s): Yuxia Pang, Xin Li, Shengwen Wang, Xueqing Qiu, Dongjie Yang, Hongming Lou
      In this paper, lignin-polyurea microcapsules (LPMC) with anti-photolysis and sustained-release performance were synthesized by interfacial polymerization based on Pickering emulsion templates of lignin particle-stabilized oil-in-water (O/W). Scanning electron microscopy (SEM) and optical microscopy (OM) images showed that LPMC was spherical in shape, with a double layer structure of a loose outer layer and a dense inner layer and its mean diameter was 10–100μm. Fourier transform infrared spectroscopy (FTIR) indicated that lignin had successfully participated in the interfacial polymerization of polyurea. LPMC were used to encapsulate avermectin (AVM), a kind of photosensitive pesticide. According to the experiment results of sustained release and anti-photolysis performance, the AVM cumulative release amount of AVM@lignin-polyurea microcapsules (AVM@LPMC) was 85% more than that of AVM@polyurea microcapsules (AVM@PMC) 50% after 72h. And the effective AVM retention rate of AVM@LPMC reached as high as 72%, while that of AVM@PMC was only 30% under UV radiation for 120h.

      PubDate: 2018-02-05T14:40:05Z
      DOI: 10.1016/j.reactfunctpolym.2017.12.018
      Issue No: Vol. 123 (2018)
       
  • Cross-linked PVC/hyperbranched polyester composite hollow fiber membranes
           for dye removal
    • Authors: Ze-Lin Qiu; Xin Kong; Jia-Jia Yuan; Yu-Jie Shen; Bao-ku Zhu; Li-Ping Zhu; Zhi-Kan Yao; Chuyang Y. Tang
      Pages: 51 - 59
      Abstract: Publication date: January 2018
      Source:Reactive and Functional Polymers, Volume 122
      Author(s): Ze-Lin Qiu, Xin Kong, Jia-Jia Yuan, Yu-Jie Shen, Bao-ku Zhu, Li-Ping Zhu, Zhi-Kan Yao, Chuyang Y. Tang
      To prepare a new type of composite membrane with high flux and good dye removal performance, hyperbranched polyester (HPE) was selected as the reactive macromonomer and a cross-linked HPE skin layer was successfully formed on the PVC-UF membrane via one-step acteal reaction between HPE and glutaraldehyde (GA) from aqueous emulsion. The resultant membranes were characterized using ATR-FTIR, FESEM, surface zeta potential and CA, while the effects of GA concentration and heat treatment time on their performance were evaluated by permeate flux and rejection rate of sunset yellow (SY). The obtained HPE-M5 membrane exhibited a SY rejection rate of 96.4% and a permeate flux of 237.6Lm−2 h−1 at 0.4MPa. Due to the good stability and the feasibility of backwashing treatment, the prepared composite hollow fiber membrane has a promising perspective of application in dye removal.

      PubDate: 2018-02-05T14:40:05Z
      DOI: 10.1016/j.reactfunctpolym.2017.10.012
      Issue No: Vol. 122 (2018)
       
  • Barrier properties and mechanical strength of bio-renewable, heat-sealable
           films based on gelatin, glycerol and soybean oil for sustainable food
           packaging
    • Authors: Emiliano M. Ciannamea; Luciana A. Castillo; Silvia E. Barbosa; María Grazia De Angelis
      Abstract: Publication date: Available online 3 February 2018
      Source:Reactive and Functional Polymers
      Author(s): Emiliano M. Ciannamea, Luciana A. Castillo, Silvia E. Barbosa, María Grazia De Angelis
      In this work we studied the mass transfer of renewable films based on gelatin (Ge), glycerol (Gly) and epoxidized soybean oil (ESO) for application in food packaging. Films were tested for water vapor absorption and diffusion at various water activities (aw), oxygen and water vapor permeability. The absorbed vapor mass increased with aw, as expected, to 0.25–0.3 g/gpol (aw = 0.8). The isotherms were fitted by five different mathematical models. The apparent diffusion coefficient showed an increasing tendency with humidity, up to aw = 0.6–0.7, where a maximum was reached. Oil addition caused a reduction in the diffusion coefficient of Ge based films, associated to a greater amount of dispersed hydrophobic phase. Moreover, heat seal and tear of Ge based films were studied. All films were able to be thermosealed. The partial replacement of Gly by 20% ESO increased significantly the heat seal strength, reaching values higher than those reported for synthetic polymers. Gelatin sample containing 20% Gly and 20% ESO presented an appropriate balance between gas barrier properties as well as the resistance of the heat sealing and the tearing.

      PubDate: 2018-02-05T14:40:05Z
      DOI: 10.1016/j.reactfunctpolym.2018.02.001
       
  • Anti-Rhizoctonia solani activity by polymeric quaternary ammonium salt and
           its mechanism of action
    • Authors: Chenyun Dong; Wanling You; Ruqi Liuyang; Yufeng Lei; Anqiang Zhang; Yaling Lin
      Abstract: Publication date: Available online 1 February 2018
      Source:Reactive and Functional Polymers
      Author(s): Chenyun Dong, Wanling You, Ruqi Liuyang, Yufeng Lei, Anqiang Zhang, Yaling Lin
      Polymeric quaternary ammonium salts (PQASs) exhibit antibacterial action and are less toxic, less stimulatory to the human body and have easier-to-modify functionalities than small molecular antibacterial agents. However, few studies on the structure-activity relationship and toxicity mechanism of PQASs against fungi have been reported. We previously described the synthesis of a novel PQAS, namely, a homopolymer of (2-methacrylamido)propyltetrabenzyldimethylammonium chloride (PQD-BC), and discovered that the polymer exhibits antifungal activities not only against Fusarium oxysporum f. sp. Cubense tropical race 4 (Foc 4), the pathogen of banana wilt, but also against Rhizoctonia solani (R. solani), the pathogen of rice sheath blight (RShB). Furthermore, we studied the mechanism of action of PQD-BC against Foc 4, which is markedly different from R. solani in morphology and life cycle. Therefore, the structure-antifungal activity relationship and toxicity mechanism of PQD-BC against R. solani were extensively studied in this work and compared with those of the low-molecular-weight quaternary ammonium salt benzyldimethyldodecylammonium chloride (BC), and the results play an important role in identifying long-term and low-toxicity fungicides that can suppress the sclerotia of R. solani. The results showed that PQD-BC and BC can destroy the structural integrity and morphology of a cell, such as by loss of the cell wall and plasma membrane integrity, leading to the release of intracellular contents and can induce mitochondrial dysfunction and interference with genomic DNA and inhibit the formation of sclerotia. However, PQD-BC showed a special mechanism for causing the lipid peroxidation of the cell membrane; this mechanism was not observed with BC. The newly elucidated mechanism accounts for differences between polymers and small-molecule compounds and provides a theoretical basis for further application of PQAS against fungi and sclerotia.
      Graphical abstract image

      PubDate: 2018-02-05T14:40:05Z
      DOI: 10.1016/j.reactfunctpolym.2018.01.020
       
  • Preparation of conjugated poly(p-phenylene) hierarchical microspheres by
           nonsolvent vapor self-assembly and their fluorescent detection of metal
           ions
    • Authors: Weibin Bai; Rijin Yao; Meiqin Guan; Xianhuo Shang; Ningshan Lai; Yanlian Xu; Jinhuo Lin
      Pages: 105 - 118
      Abstract: Publication date: Available online 14 November 2017
      Source:Reactive and Functional Polymers
      Author(s): Weibin Bai, Rijin Yao, Ningshan Lai, Xianhuo Shang, Yanlian Xu, Jinhuo Lin
      The novel hierarchical microspheres from conjugated poly(p-phenylene)s can be self-assembled by the nonsolvent vapor method. The formation of hierarchical microspheres depends on the choice of polar nonsolvent vapor atmospheres, solvents, and the length of side chains. The intermolecular interactions, including the side-chain interactions and the π–π interactions between conjugated backbones, occur spontaneously to form various conformations and polymeric aggregates, which have an effect on the fluorescence wavelength of the polymer hierarchical microspheres. Our results demonstrate a facile way to prepare polymeric hierarchical microspheres and adjust their optical properties. Moreover, the hierarchical microspheres with rough surface show a highly selective fluorescence “turn-off” sensor for Fe3+ with almost no interference of other metal ions.

      PubDate: 2017-11-19T01:00:17Z
      DOI: 10.1016/j.eurpolymj.2017.08.016
      Issue No: Vol. 95 (2017)
       
  • Synthesis and characterization of phosphorus-containing, silicone rubber
           based flame retardant coatings
    • Authors: R. Januszewski; M. Dutkiewicz; H. Maciejewski; B. Marciniec
      Pages: 1 - 9
      Abstract: Publication date: February 2018
      Source:Reactive and Functional Polymers, Volume 123
      Author(s): R. Januszewski, M. Dutkiewicz, H. Maciejewski, B. Marciniec
      The synthesis and characterization of two biphenyl phosphates of different structures, as substrates for preparation of two series of functionalized addition silicone rubbers of different crosslink density and amount of pendant functional groups, is presented. Obtained materials were applied as flame retardant protective coatings for cotton fabric and characterized by TG and MMC techniques. The relationship between thermal stability, flame-retardant properties, and structure of prepared silicone rubbers is discussed.

      PubDate: 2017-12-17T17:54:55Z
      DOI: 10.1016/j.reactfunctpolym.2017.12.006
      Issue No: Vol. 123 (2017)
       
  • On the enhanced corrosion resistance of elastomer-modified
           polybenzoxazine/graphene oxide nanocomposite coatings
    • Authors: Eugene B. Caldona; Al Christopher C. de Leon; Joey D. Mangadlao; Kramer Joseph A. Lim; Bryan B. Pajarito; Rigoberto C. Advincula
      Pages: 10 - 19
      Abstract: Publication date: February 2018
      Source:Reactive and Functional Polymers, Volume 123
      Author(s): Eugene B. Caldona, Al Christopher C. de Leon, Joey D. Mangadlao, Kramer Joseph A. Lim, Bryan B. Pajarito, Rigoberto C. Advincula
      In this study, we demonstrate the use of rubber-modified polybenzoxazine (PBZ)/graphene oxide (GO) as a coating to protect carbon steel from corrosion. GO, acting as the nanofiller, is added in increasing amounts to enhance the barrier property of the resulting nanocomposite coatings. Results via immersion in chloride solution coupled with standard electrochemical measurements show that the rubber-modified PBZ is able to protect carbon steel from corrosion attack. Even more, the coatings containing small amounts of GO provided enhanced protective abilities for the carbon steel. By varying the amount of GO, the protective property is tuned and the optimum GO concentration that could offer the most enhanced corrosion resistance property is determined.
      Graphical abstract image

      PubDate: 2017-12-17T17:54:55Z
      DOI: 10.1016/j.reactfunctpolym.2017.12.004
      Issue No: Vol. 123 (2017)
       
  • Laccase modified lignosulfonates as novel binder in pigment based paper
           coating formulations
    • Authors: Andreas Ortner; Karin Hofer; Wolfgang Bauer; Gibson S. Nyanhongo; Georg M. Guebitz
      Pages: 20 - 25
      Abstract: Publication date: February 2018
      Source:Reactive and Functional Polymers, Volume 123
      Author(s): Andreas Ortner, Karin Hofer, Wolfgang Bauer, Gibson S. Nyanhongo, Georg M. Guebitz
      The exploitation of renewable and cheaper paper coating formulations especially for graphic paper products is gaining increasing importance due to concerns regarding the use of fossil based raw materials. For this reason, a novel process for enzymatic modification of lignosulfonates to substitute fossil based styrene-butadiene (SB) latex as binders in conventional paper coating formulations was developed. Laccase polymerization of ultrafiltrated lignosulfonates (LS) resulted in an increase of the molecular weight from an average of 26kDa to 170kDa as compared to non-ultrafiltrated LS which increased from 5.7kDa to 76kDa. When used in coating formulations, laccase polymerized LS resulted in coated paper with improved printing properties (reduced picking compared to non polymerized LS) provided that the LS was ultrafiltrated before polymerization. Abo Akademi gravimetric water retention properties of the paper coatings were comparable (395g m−2) to those obtained with reference latex (350g m−2). Similarly, cross sectional fluorescence microscopy images showed that ultrafiltration prior to laccase polymerization reduced penetration of the polymerized lignosulfonates into the base paper to 33% and additionally reduced polymerization time from 6h to 2h. These results demonstrate the possibility of substituting fossil based styrene-butadiene (SB) latex binders with on-site produced lignosulfonates which have traditionally been considered so far mainly as a by-product used for energy production in the pulp and paper industry.

      PubDate: 2017-12-17T17:54:55Z
      DOI: 10.1016/j.reactfunctpolym.2017.12.005
      Issue No: Vol. 123 (2017)
       
  • In situ complexation versus complex isolation in synthesis of ion
           imprinted polymers
    • Authors: Katri Laatikainen; Catherine Branger; Bruno Coulomb; Véronique Lenoble; Tuomo Sainio
      Pages: 1 - 8
      Abstract: Publication date: January 2018
      Source:Reactive and Functional Polymers, Volume 122
      Author(s): Katri Laatikainen, Catherine Branger, Bruno Coulomb, Véronique Lenoble, Tuomo Sainio
      In this study, the object is to prove that isolation of complexes made by varying the metal/ligand ratio (in situ complexation) yields similar polymer characteristics, metal binding and selectivity results as polymers synthesized by isolating the complex by precipitation. Complexation between nickel and the N-(4-vinylbenzyl)-2-(aminomethyl)pyridine (Vbamp) monomer was studied in dimethyl sulfoxide (DMSO) and in a DMSO-methanol mixture (50:50, v/v) at 80°C using a Ni(NO3)2·6H2O salt as the nickel source. According to the results, the three nickel/Vbamp complexes could be selectively obtained using specific conditions: for [Ni(Vbamp)]2+ the Ni/Vbamp ratio in DMSO was 1.08, for [Ni(Vbamp)2]2+ the Ni/Vbamp ratio DMSO-methanol (50:50, v/v) was 0.49 and for [Ni(Vbamp)3]2+ the Ni/Vbamp ratio in DMSO was 0.3. Ion-imprinted polymers (IIPs) were prepared either with [Ni(Vbamp)](NO3)2, [Ni(Vbamp)2](NO3)2, or [Ni(Vbamp)3](NO3)2 complexes as the template. IIP with a [Ni(Vbamp)3]2+ complex, isolated by precipitation prior to polymerization, was also prepared. The results demonstrated that surface properties, nickel binding and selectivity properties were similar for both kind of IIPs – prepared by in situ complexation or isolation of the complex prior to polymer synthesis. Selectivity coefficients of nickel toward zinc for IIPs with [Ni(Vbamp)]2+, [Ni(Vbamp)2]2+ and [Ni(Vbamp)3]2+ templates were close to 1038, 1441 and 1463, respectively.

      PubDate: 2017-11-19T01:00:17Z
      DOI: 10.1016/j.reactfunctpolym.2017.10.022
      Issue No: Vol. 122 (2017)
       
  • Investigation on pH/salt-responsive multifunctional itaconic acid based
           polymeric biocompatible, antimicrobial and biodegradable hydrogels
    • Authors: M. Sakthivel; D.S. Franklin; S. Sudarsan; G. Chitra; T.B. Sridharan; S. Guhanathan
      Pages: 9 - 21
      Abstract: Publication date: January 2018
      Source:Reactive and Functional Polymers, Volume 122
      Author(s): M. Sakthivel, D.S. Franklin, S. Sudarsan, G. Chitra, T.B. Sridharan, S. Guhanathan
      The present investigation focused on a new kind of pH-tunable IAD polymeric hydrogels based on itaconic acid (IA), acrylic acid (AA) and diethylene glycol (DEG), were synthesized by free radical polymerization viz. organic solventless approach and they were characterized by FT-IR, SEM analysis. For successive biocompatible hydrogels, biological activities were mainly considered for investigation. The swelling studies showed that the IAD hydrogels exhibited significantly greater pH-responsive swelling in alkaline medium and achieved up to 2200%. The salt responsive behaviour of IAD hydrogels proved that the results of swelling equilibrium decreased with increasing charge of the cation. Since, the prepared hydrogels were anionic in nature, excellent antibacterial zone of inhibition achieved towards gram +ve pathogens. It was found that the IAD hydrogels were performed better antifungal zone of inhibition against C. albicans. The IAD hydrogels pronounced noticeable zone of inhibition towards various pathogens even for pristine (without antibiotic) samples. The prepared itaconic acid based hydrogels were nontoxic due to their IC-50% values. The IAD hydrogels underwent for biodegradation due to n-number of ester moieties. It facilitated, hydrolysis of polymeric skeleton and achieved 88% of degradation. It was found that IA based pH-sensitive polymeric hydrogels were nontoxic with aggregable biomedical properties.
      Graphical abstract image

      PubDate: 2017-11-19T01:00:17Z
      DOI: 10.1016/j.reactfunctpolym.2017.10.021
      Issue No: Vol. 122 (2017)
       
  • A comparative study of polyethylene terephthalate surface carboxylation
           techniques: Characterization, in vitro haemocompatibility and
           endothelialization
    • Authors: Balaji Ramachandran; Sudip Chakraborty; Madhulika Dixit; Vignesh Muthuvijayan
      Pages: 22 - 32
      Abstract: Publication date: January 2018
      Source:Reactive and Functional Polymers, Volume 122
      Author(s): Balaji Ramachandran, Sudip Chakraborty, Madhulika Dixit, Vignesh Muthuvijayan
      Surface functionalization of polymers is crucial for improving biocompatibility and haemocompatibility, which correlates to improved performance of medical devices. Here, we have evaluated the effect of four PET surface carboxylation techniques on the antifouling property, haemocompatibility, and endothelialization. Surface carboxylation was achieved by formaldehyde+bromoacetic acid treatment (PET-1[COOH]), methacrylic acid grafting (PET-2[COOH]), NaOH hydrolysis+KMnO4 oxidation (PET-3[COOH]), and oxygen plasma treatment+acrylic acid grafting (PET-4[COOH]). The carboxyl densities on these surfaces were 0.4, 23.2, 31.9, 16.4nmol/cm2, respectively. XPS and FTIR spectroscopy confirmed the introduction of carboxyl groups. Water contact angle results showed that hydrophilicity increased with an increase in surface carboxyl density. SEM images confirmed that these modifications didn't cause any surface deterioration. AFM studies showed an increase in surface roughness of the carboxylated PET. Tensile testing showed that these modifications did not affect the bulk properties. Compared to control, PET-3[COOH] has a 9-fold reduction in BSA adsorption. Haemocompatibility studies showed significantly reduced %hemolysis and platelet adhesion on the carboxylated PET. Cell culture studies revealed that endothelial cell (EA.hy926) attachment increased with increase in surface carboxyl density. PET-3[COOH] showed the most improved haemocompatibility and endothelial cell attachment. These results clearly show that the method of functionalization has a significant impact on the haemocompatibility and cell attachment.

      PubDate: 2017-11-19T01:00:17Z
      DOI: 10.1016/j.reactfunctpolym.2017.11.001
      Issue No: Vol. 122 (2017)
       
  • Biodegradable photocross-linked polymers of glycerol diglycidyl ether and
           structurally different alcohols
    • Authors: Sigita Kasetaite; Jolita Ostrauskaite; Violeta Grazuleviciene; Danguole Bridziuviene; Ruta Budreckiene; Egidija Rainosalo
      Pages: 42 - 50
      Abstract: Publication date: January 2018
      Source:Reactive and Functional Polymers, Volume 122
      Author(s): Sigita Kasetaite, Jolita Ostrauskaite, Violeta Grazuleviciene, Danguole Bridziuviene, Ruta Budreckiene, Egidija Rainosalo
      Structurally different alcohols, e.g. 1,4-cyclohexanedimethanol, 1,1,1-tris(hydroxymethyl)propane, hydroquinone, and bisphenol A, were used for photocross-linking of glycerol diglycidyl ether on purpose to study structure-properties relationship of the resulting polymer films. Kinetics of photocross-linking was investigated by photorheometry. Dependencies of chemical structure and amount of alcohol used on mechanical, thermal, rheological properties, and biodegradability of the synthesized polymers were studied. The addition of alcohol resulted in an increase of the rate of photocross-linking of glycerol diglycidyl ether. The amount of alcohol used had more considerable effect on properties of polymers than chemical structure of alcohol. The higher amount (>20mol%) of alcohol led to the easier association of alcohol molecules with released protons and thus deteriorated the properties of the cross-linked polymers. However, the addition of alcohols increased the biodegradability of resulted polymers.

      PubDate: 2017-12-17T17:54:55Z
      DOI: 10.1016/j.reactfunctpolym.2017.11.005
      Issue No: Vol. 122 (2017)
       
  • Curing kinetics and characterization of dual-curable thiol-acrylate-epoxy
           thermosets with latent reactivity
    • Authors: Ali Osman Konuray; Xavier Fernández-Francos; Xavier Ramis
      Pages: 60 - 67
      Abstract: Publication date: January 2018
      Source:Reactive and Functional Polymers, Volume 122
      Author(s): Ali Osman Konuray, Xavier Fernández-Francos, Xavier Ramis
      A new dual-curing scheme was developed for thiol-acrylate-epoxy mixtures. A photo-initiated latent catalytic system was used to carry out thiol-acrylate Michael addition at 35°C (Stage 1) followed by thiol-epoxy click reaction (Stage 2) at 80–110°C. The intermediate materials were shown to have several days of storage stability. The use of a radical inhibitor has suppressed radical mediated acrylate homopolymerization which would otherwise lead to unreacted thiols remaining. Kinetics of Stage 2 was analyzed mathematically using isoconversional differential method and Kamal model regression. Glass transition temperatures (T g ) of samples with varying contents of epoxy and different types of acrylates were measured. Epoxy-rich formulations gave the highest final T g . Although not as influential as the epoxy content, using higher functional and more rigid acrylate monomers resulted in higher intermediate and final T g . The proposed curing scheme and the resulting materials could be useful in applications such as adhesives, industrial coatings with high chemical resistance, optical and electronic materials.

      PubDate: 2017-12-17T17:54:55Z
      DOI: 10.1016/j.reactfunctpolym.2017.11.010
      Issue No: Vol. 122 (2017)
       
  • Polysiloxane graft polyethylene synthesized by a novel heterofunctional
           condensation approach
    • Authors: Yongjie Zhang; Xiaopei Li; Wenbo Wang; Shuwei Wang; Jing Xu; Longquan Xu; Huayi Li
      Pages: 68 - 74
      Abstract: Publication date: January 2018
      Source:Reactive and Functional Polymers, Volume 122
      Author(s): Yongjie Zhang, Xiaopei Li, Wenbo Wang, Shuwei Wang, Jing Xu, Longquan Xu, Huayi Li
      Polysiloxane/polyethylene graft copolymers can synergistically combine the distinguished properties obtained separately in polyethylene (PE) and polysiloxane and therefore attract considerable attentions from both academia and industry. Herein, we introduce a novel and efficient heterofunctional condensation approach to synthesize well-defined polydimethylsiloxane graft PE (PDMS-g-PE) under mild conditions. The chemical structures of PDMS-g-PE are characterized unambiguously, and the correlation between reaction conditions and the structural parameters of PDMS-g-PE is established. Scanning electron microscope images show that the obtained graft copolymer PDMS-g-PE can compatibilize the immiscible PE/silicone oil system.
      Graphical abstract image

      PubDate: 2017-12-17T17:54:55Z
      DOI: 10.1016/j.reactfunctpolym.2017.11.006
      Issue No: Vol. 122 (2017)
       
  • Swelling and methylene blue adsorption of
           poly(N,N-dimethylacrylamide-co-2-hydroxyethyl methacrylate) hydrogel
    • Authors: A.R. Hernandez-Martínez; J.A. Lujan-Montelongo; C. Silva-Cuevas; Josué D. Mota-Morales; M. Cortez-Valadez; Álvaro de Jesus Ruíz-Baltazar; M. Cruz; Jorge Herrera-Ordonez
      Pages: 75 - 84
      Abstract: Publication date: January 2018
      Source:Reactive and Functional Polymers, Volume 122
      Author(s): A.R. Hernandez-Martínez, J.A. Lujan-Montelongo, C. Silva-Cuevas, Josué D. Mota-Morales, M. Cortez-Valadez, Álvaro de Jesus Ruíz-Baltazar, M. Cruz, Jorge Herrera-Ordonez
      Dyes from wastewater have a negative impact on health and environment, even at low concentrations. Several methods have been proposed for their removal, one of them is using hydrogels as adsorbents for wastewater treatment. In this work, we propose N,N-dimethylacrylamide and 2-hydroxyethyl methacrylate copolymer (p(HEMA-co-DMAa)) as an adsorbent alternative. Swelling behavior as function of pH and temperature was studied. Morphological characterization of crosslinked copolymer and its hydrogel structure were performed by SEM analysis and FTIR spectroscopy. Swelling measurements and sorption studies were made using methylene blue (as cationic dye model) under different medium pH. Results from confocal images of swollen p(HEMA-co-DMAa) in methylene blue solutions indicate a macroporous material formed. The dye diffuses homogeneously through the entire hydrogel during swelling. The p(HEMA-co-DMAa) hydrogels were able to uptake up to 3.6 times their weight of water depending on temperature; the lower the equilibrium temperature the higher the water uptake. P(HEMA-co-DMAa) hydrogels adsorption capacity is competitive compared with other adsorbents already reported. It was determined that the LCST of the hydrogel at 321K and the formation of a complex at pH=8. The optimal removal time was at 4h after the copolymer was added. The hydrogel was stable (as suggested by FTIR spectrum) and able to uptake methylene blue in a wide pH range. Therefore, it is suitable as adsorbent alternative; additionally, the p(HEMA-co-DMAa) hydrogels would be environmentally friendly due to their biocompatibility and non-cytotoxicity.

      PubDate: 2017-12-17T17:54:55Z
      DOI: 10.1016/j.reactfunctpolym.2017.11.008
      Issue No: Vol. 122 (2017)
       
  • Design of long-chain branched copolyesters and manufacture as well as
           physical properties of their extrusion films
    • Authors: Chiu-Chun Lai; Chun-Ta Yu; Meng-Hsin Chen; Hsin-Lung Chen; Fu-Ming Wang; Chih-Hsiang Lin; Lung-Chang Liu; Chien-Ming Chen
      Pages: 98 - 106
      Abstract: Publication date: January 2018
      Source:Reactive and Functional Polymers, Volume 122
      Author(s): Chiu-Chun Lai, Chun-Ta Yu, Meng-Hsin Chen, Hsin-Lung Chen, Fu-Ming Wang, Chih-Hsiang Lin, Lung-Chang Liu, Chien-Ming Chen
      A long-chain branched copolyester (i.e. p-hydroxybenzoic acid (HBA)/2-hydroxy-6-naphthoic acid (HNA)/1,1,1-tris(4-hydroxyphenyl)ethane (THPE) copolyester) and its extrusion film with superior physical properties to commercial Ticona A950 and Vecstar CTZ have been manufactured by the design of appropriate prescriptions, T-Die extrusion, and thermal treatment of crystal transformation. In order to investigate the fabricating feasibility for flexible copper clad laminate (FCCL) of fourth/fifth generation long-term evolution (4G/5G LTE), we have also agglutinated lab-made copolyester extrusion film with the copper foil by hot compression. Experimental results manifest that lab-made copolyester extrusion film is a highly potential FCCL substrate of 4G/5G LTE because its thickness, dielectric constant (Dk), dielectric loss (Df), hygroscopicity, yellowness index (YI), antistatic capability, flammability, melting temperature (Tm), coefficient of thermal expansion (CTE), and peel strength to copper foil are 50μm, 2.90, 0.00140, 0.04%, 2.7, 6.5×109 Ω/□, UL-94 V0, 305°C, 24.8ppm/°C, and 29.9lb/in, respectively.

      PubDate: 2017-12-17T17:54:55Z
      DOI: 10.1016/j.reactfunctpolym.2017.11.007
      Issue No: Vol. 122 (2017)
       
  • Superheated solutions in dual-temperature ion exchange separations
    • Authors: V.A. Ivanov; E.A. Karpyuk; O.T. Gavlina; S.I. Kargov
      Pages: 107 - 115
      Abstract: Publication date: January 2018
      Source:Reactive and Functional Polymers, Volume 122
      Author(s): V.A. Ivanov, E.A. Karpyuk, O.T. Gavlina, S.I. Kargov
      The problem of experimental determination of the differential enthalpy of ion exchange is considered. The determination of the enthalpy from experimental equilibrium coefficients is characterized by a high degree of error. A considerably more accurate method of determination of the differential enthalpy of ion exchange on selective ion exchangers is proposed. The method is based on the analysis only of the composition of the solution in the equilibrium system at two temperatures. The influence of temperature on the exchange of mono- and divalent ions on polyacrylic and polymethacrylic cation exchangers within the range from 273K to 400K is studied. It is shown than for all exchangers under study the differential enthalpy linearly increases with temperature. The role of the increase of Δ H n ¯ with temperature in the process of a single-step dual-temperature separation is estimated. It is found that the increase of the upper temperature boundary leads to a very sharp increase of the degree of dual-temperature separation. This effect is most pronounced in superheated solutions. It is shown that when predicting changes in selectivity with temperature and the extent of purification of solutions of alkali metal salts from admixtures of divalent ions, it is necessary to take the temperature dependence of the ion exchange enthalpy into account.

      PubDate: 2017-12-17T17:54:55Z
      DOI: 10.1016/j.reactfunctpolym.2017.11.009
      Issue No: Vol. 122 (2017)
       
  • Immobilization of poly(N-acryoyl morpholine) via hydrogen-bonded
           interactions for improved separation and antifouling properties of
           poly(vinylidene fluoride) membranes
    • Authors: Yang He; Xi Chen; Fengying Dai; Rui Xu; Ning Yang; Xia Feng; Yiping Zhao; Li Chen
      Abstract: Publication date: Available online 24 December 2017
      Source:Reactive and Functional Polymers
      Author(s): Yang He, Xi Chen, Fengying Dai, Rui Xu, Ning Yang, Xia Feng, Yiping Zhao, Li Chen
      Poly(N-acryoyl morpholine) (PACMO), a promising antifouling surface modifier, has many desirable properties including high hydrophilicity, chemical stability, and excellent hemocompatibility. Considering the intrinsic hydrophobic property of most polymer membranes, surface modification by hydrogen bonding self-assembly has garnered intense interest. In this work, a hydrophobic poly(vinylidene fluoride) (PVDF) membrane surface was first dip-coated a polydopamine (PDA) coating and then followed by immobilization of PAMCO via hydrogen-bonded interactions between PACMO and PDA. The mechanism of foulants deposition onto the membrane surface was quantitatively assessed by extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory. The hydrophilic PACMO layer modified PVDF membranes exhibited a simultaneously enhanced permeability, rejection and antifouling property in protein filtration and oil/water emulsion filtration, and humic acid filtration, respectively. Moreover, the as-prepared membranes had prominent long-term stability even in harsh conditions due to strong hydrogen-bonded interactions between PACMO and PDA. This work provided a practical strategy for hydrophilizing membrane surfaces by hydrogen bonding self-assembly.

      PubDate: 2017-12-26T18:31:41Z
      DOI: 10.1016/j.reactfunctpolym.2017.12.014
       
  • An augmented delivery of the anticancer agent, curcumin, to the colon
    • Authors: Rayan Sabra; Nashiru Billa; Clive J. Roberts
      Abstract: Publication date: Available online 20 December 2017
      Source:Reactive and Functional Polymers
      Author(s): Rayan Sabra, Nashiru Billa, Clive J. Roberts
      This work describes the formulation aspects of an orally viable curcumin-containing mucoadhesive nanoparticulate system for management of colon cancer. Curcumin is documented to possess anticancer properties whilst modified citrus pectin yields a galactose functionality capable of inhibiting the growth and proliferation of colon cancer cells due to antagonism to galectin-3 (Gal-3). A successfully formulated curcumin containing chitosan-modified citrus pectinate nanoparticles (MCPCNPs) registered a z-average of 178nm (±0.896) and a positive surface charge of +35.7mV (±1.41). The MCPCNPs presented high mucoadhesion propensity in the colonic region/media and minimal at pH1.2 (stomach). There was approximately 18% curcumin release at pH1.2 over 2h and up to 68% release in the 33% (w/v) caecal medium over 24h. The data obtained strongly suggests that the formulated MCPCNPs have the potential to be applied as an orally deliverable colon cancer formulation alternative in the treatment of colon cancer.
      Graphical abstract image

      PubDate: 2017-12-26T18:31:41Z
      DOI: 10.1016/j.reactfunctpolym.2017.12.012
       
  • Complexation with whey protein hydrolysate improves cacao pods husk pectin
           surface active and emulsifying properties
    • Authors: Daniel Trujillo-Ramírez; Consuelo Lobato-Calleros; Angélica Román-Guerrero; Landy Hernández-Rodríguez; Jose Alvarez-Ramirez; Eduardo J. Vernon-Carter
      Abstract: Publication date: Available online 19 December 2017
      Source:Reactive and Functional Polymers
      Author(s): Daniel Trujillo-Ramírez, Consuelo Lobato-Calleros, Angélica Román-Guerrero, Landy Hernández-Rodríguez, Jose Alvarez-Ramirez, Eduardo J. Vernon-Carter
      Pectin was extracted from cacao pod husks (CPHP) wastes, having a methylesterification degree of 83.22%, acetylation degree of 10.20%, and protein content of 3.68%. The adsorption dynamics of CPHP at the canola oil-water interface were studied, and diffusion (k diff ), penetration (k pen ) and rearrangement (k rea ) rate constants were determined. Canola oil-in-water (O/W) emulsions (ECPHP) were stabilized which CPHP, and exhibited an initial area-volume mean diameter (d3,2) of 113.60nm, which increased to 162.0nm during 28days of storage. CPHP was electrostatically complexed with whey protein hydrolysate (WPH) in a weight ratio 5:1 and pH3.25, in order to improve the surface active and emulsifying activities. The soluble complex (SCWPH-CPHP) decreased the interfacial tension faster and to a lower value, and displayed higher k diff and k pen than CPHP. SCWPH-CPHP yielded O/W emulsions with d3,2 <90nm, which did not suffer significant changes in oil droplet size during storage. The apparent viscosity of SCWPH-CPHP aqueous dispersion was much lower than that of CPHP dispersion. The zeta potential of EWPH-CPHP was lower than for ECPHP. Thus, it was concluded that the greater stability of EWPH-CPHP was due mainly to steric repulsion originated by the soluble complex adsorption layers around the oil droplets.
      Graphical abstract image

      PubDate: 2017-12-26T18:31:41Z
      DOI: 10.1016/j.reactfunctpolym.2017.12.011
       
  • Hybrid cross-linked poly(2-acrylamido-2-methyl-1-propanesulfonic acid)
           hydrogels with tunable viscoelastic, mechanical and self-healing
           properties
    • Authors: Esra Su; Oguz Okay
      Abstract: Publication date: Available online 19 December 2017
      Source:Reactive and Functional Polymers
      Author(s): Esra Su, Oguz Okay
      Hydrogels derived from 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) monomer are attractive materials for producing soft-biomimetic actuators, superabsorbents, and biomaterials. Here we present a simple synthetic strategy to prepare mechanically strong poly(2-acrylamido-2-methyl-1-propanesulfonic acid) (PAMPS) hydrogels with self-healing ability. Initiator-free polymerization of AMPS in aqueous solution in the presence of Laponite nanoparticles and N,N′-methylenebis(acrylamide) (BAAm) cross-linker produces hybrid-cross-linked hydrogels with excellent mechanical properties. The hydrogels exhibit a high modulus (~700kPa), compressive strength (45MPa at ~90% strain), good resilience, and self-healing. The results reveal that the incorporation of Laponite and BAAm separately into the physical PAMPS network weakens hydrogen bonding interactions while their combination enhances these interactions and generate water-insoluble hydrogels with a high modulus. The superior properties of hybrid cross-linked hydrogels are attributed to strengthening of the interactions between chemically cross-linked PAMPS chains and nanoparticles. The hybrid approach presented here might enable preparation of mechanically strong nanocomposite hydrogels consisting of strongly or weakly charged polymer chains of different architecture.

      PubDate: 2017-12-26T18:31:41Z
      DOI: 10.1016/j.reactfunctpolym.2017.12.009
       
  • Hydrolytically degradable POSS-PEG hybrid hydrogels prepared in aqueous
           phase with tunable mechanical properties, swelling ratio and degradation
           rate
    • Authors: Jinrui Shen; Heling Li; Cuifen Lu; Guichun Yang; Feiyi Wang; Junqi Nie; Xingjian Hu; Nianguo Dong; Jiawei Shi
      Abstract: Publication date: Available online 18 December 2017
      Source:Reactive and Functional Polymers
      Author(s): Jinrui Shen, Heling Li, Cuifen Lu, Guichun Yang, Feiyi Wang, Junqi Nie, Xingjian Hu, Nianguo Dong, Jiawei Shi
      A series of hydrolytically degradable polyhedral oligomeric silsesquioxanes (POSS)-poly(ethylene glycol) (PEG) hybrid hydrogels were prepared by covalently grafting hydrophobic POSS onto hydrophilic 4-arm-PEG-maleimide to form an amphipathic precursor and further cross-linking with hydrolytically PEG-diester-dithiol via Michael-type addition. The process to form hydrogels was in aqueous phase completely, which is free of metal catalyst, UV irradiation, and organic solvents. In addition, POSS as enhanced agents, only small amounts are needed to cause significant changes in hydrogels properties due to the special surface properties and high mechanical stability of the nanosize particles. Experimental results showed that by increasing the mass fraction of POSS from 0% to 4%, the storage modulus (G′) of the hybrid hydrogels have observably increased from 250Pa to 1800Pa. Furthermore, the hybrid hydrogels exhibited a good water absorption capacity and they can be degraded by hydrolysis. The swelling ratio of the hybrid hydrogels decreased with the increase of the POSS content and the microstucture of hybrid hydrogels is also dominated by the POSS content. The degradation rate can be tuned by the POSS content, and a higher POSS content corresponds to a slower degradation rate.

      PubDate: 2017-12-26T18:31:41Z
      DOI: 10.1016/j.reactfunctpolym.2017.12.008
       
  • Quinone based oligomeric sensors as colorimetric probes for cyanide anion:
           Effects of solvent medium and substituent on sensing
    • Authors: P. Madhusudhana Reddy; Shih-Rong Hsieh; Wan-Chi Wu; Chi-Jung Chang; Yi-Shao Chen; Ming-Ching Lee
      Abstract: Publication date: Available online 13 December 2017
      Source:Reactive and Functional Polymers
      Author(s): P. Madhusudhana Reddy, Shih-Rong Hsieh, Wan-Chi Wu, Chi-Jung Chang, Yi-Shao Chen, Ming-Ching Lee
      The main objective of the present study is to understand the structure-property relationships of sensor capable of colorimetric response, upon the addition of particular anions, due to hydrogen-bonding association between sensor and anion. Further, hydrogen-bonding association between sensor and anion, and thereby colorimetric response of the receptor in various solvent media was also targeted. For this, we have synthesized chloro-substituted quinone based oligomer sensor (QO-Cl) and cyano-substituted quinone based oligomer sensor (QO-CN), which contain the thiourea as a binding site. These oligomeric sensors were exploited as colorimetric sensors for cyanide anion [CN−]. Further, the sensing abilities of these sensors for CN− recognition in various solvents were monitored to investigate the influence of solvent on the hydrogen bonding association between sensor and anion. Our colorimetric and spectrometric results unveiled that the QO-CN sensor has shown the better binding constant (KQO-CN-CN −=39,317M−1) and detection of limit (DOL=1.2μM) for CN− than that of QO-Cl, (KQO-Cl-CN −=1950M−1; DOL=69μM). This can be attributed to the higher electron withdrawing nature of CN than the moderately electron-withdrawing substituent Cl.
      Graphical abstract image

      PubDate: 2017-12-17T17:54:55Z
      DOI: 10.1016/j.reactfunctpolym.2017.12.007
       
  • Branched dicationically-charged phosphodicholine (PdC) modified chitosan
           with specific associated water structure and unique interactions with
           biocomponents
    • Authors: Xingwen Huang; Bangren Fang; Zehang Xu; Zhaoyu Cao; Rong Zeng; Mei Tu; Jianhao Zhao
      Abstract: Publication date: Available online 7 December 2017
      Source:Reactive and Functional Polymers
      Author(s): Xingwen Huang, Bangren Fang, Zehang Xu, Zhaoyu Cao, Rong Zeng, Mei Tu, Jianhao Zhao
      Cationic polymers possess significant potential in various biomedical applications due to their favorable interactions with biocomponents in aqueous media, which is related to their inherent structure and associated water structure. This work presents the development of a novel biodegradable cationic polymer with specific associated water structure and unique interactions with biocomponents. Bioinspired branched dicationically-charged phosphodicholine-chitosan (PdCCs) with different substitute degree were synthesized via Atherton-Todd reaction. As compared with monocationically charged N-(2-hydroxyl) propyl-3-trimethyl ammonium chitosan chloride (HTCC), thermal analysis confirmed the existence of the freezing bound water surrounding PdCCs due to the introduction of branched dicationically-charged PdC moiety. Fluorescence spectra revealed that PdCCs induced much less conformational change of bovine serum albumin than HTCC. Antibacterial and hemolysis assay showed that PdCCs and HTCC displayed high antibacterial activities against Escherichia coli and Staphylococcus aureus with different bacterial-type selectivity, and PdCCs showed higher selectivity to kill bacteria over red blood cell than HTCC. Furthermore, PdCCs-immobilized antibacterial surfaces exhibited better hydrophilicity and less protein adsorption than HTCC-immobilized antibacterial surfaces. These results indicated that branched dicationic PdC with capacity to restrain the freezing bound water may provide a good choice for developing cationic polymers for therapeutic applications.

      PubDate: 2017-12-17T17:54:55Z
      DOI: 10.1016/j.reactfunctpolym.2017.12.003
       
  • Enhanced magnetic behaviour and cell proliferation of gamma irradiated
           dual metal ions co-doped hydroxyapatite – poly(methyl methacrylate)
           composite films
    • Authors: J. Ramana Ramya; K. ThanigaiArul; P. Sathiamurthi; K. Asokan; N. Rajmuhon Singh; S. Narayana Kalkura
      Abstract: Publication date: Available online 5 December 2017
      Source:Reactive and Functional Polymers
      Author(s): J. Ramana Ramya, K. ThanigaiArul, P. Sathiamurthi, K. Asokan, N. Rajmuhon Singh, S. Narayana Kalkura
      The poly (methyl methacrylate) (PMMA)/Iron-Zinc co-doped nanosized hydroxyapatite (FeZn nHAp) composite films have been prepared by solvent evaporation method. The as prepared composite films were subjected to gamma irradiation at various dosages. Physico-chemical and biological characterization of the composite film were carried out. The XRD, FTIR and SEM analysis confirmed the presence of hydroxyapatite in the PMMA matrix. Irradiated composite films revealed reduced saturation magnetization (42%) and retentivity (66%) due to the defects created on irradiation. The gamma irradiated composite films showed strong antimicrobial activity on gram negative bacteria (E. coli) which may be due to the action of leakage of zinc ions on the surface that block the transport channels of the cell leading to the cell death. Moreover, substantial modification was seen in the hydrophobicity and surface roughness. The irradiations also tend to turn the samples semi conductive. The biocompatibility studies of the gamma irradiated composite films showed enhanced cell viability to NIH 3T3 fibroblast cells. Hence, the gamma irradiated samples showed excellent multifunctional properties that could be used in tissue engineering, bio-sensing and wound healing applications.

      PubDate: 2017-12-17T17:54:55Z
      DOI: 10.1016/j.reactfunctpolym.2017.11.011
       
  • Ferrofluid mediated chitosan@mesoporous carbon nanohybrid for green
           adsorption/preconcentration of toxic Cd(II): Modeling, kinetic and
           isotherm study
    • Authors: Hassan Yadaei; Mostafa Hossein Beyki; Farzaneh Shemirani; Siavash Nouroozi
      Abstract: Publication date: Available online 10 November 2017
      Source:Reactive and Functional Polymers
      Author(s): Hassan Yadaei, Mostafa Hossein Beyki, Farzaneh Shemirani, Siavash Nouroozi
      In this research an efficient ionic liquid based ferrofluid system was developed for efficient adsorption/preconcentration of cadmium using magnetic mesoporous carbon – chitosan nanohybrid. Mesoporous CMK - 3 was synthesized using MCM – 48 as ordered template. Then magnetic CMK was combined with chitosan through reaction with epichlorohydrin. The nanohybrid was characterized with FESEM, TEM, XRD, SEM mapping, FTIR, BET and VSM techniques. Effective parameters on cadmium adsorption was optimized with response surface methodology (RSM) using Box – Behnken design. Solution pH, contact time, adsorbent dosage and ionic strength were four studied variables on cadmium adsorption. Results showed that all studied variables are significant on cadmium adsorption. Isotherm study was performed at optimum conditions (pH=8, time 3min, adsorbent dosage 13mg and ionic strength of 0.15%) based four isotherm models and results showed that cadmium adsorption followed the order of Redlich–Peterson>Freundlich>Langmuir>Dubinin–Radushkevich with maximum adsorption capacity of 251.9mgg−1. Results for kinetic study confirmed that pseudo second order model can better describe cadmium adsorption. Regeneration of the sorbent was performed with HNO3 solution (1.0molL−1). Finally developed adsorption process was employed for cadmium preconcentration from real samples.

      PubDate: 2017-11-19T01:00:17Z
      DOI: 10.1016/j.reactfunctpolym.2017.10.011
       
 
 
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